Religious traditions across history have commonly developed rituals around purity and how to properly bury the dead: quite often, these areas overlapped. In the ancient period of the Zoroastrian religion (developing in modern Iran), records of disposing human corpses in a non-polluting way were documented as early as the fifth century BCE. Zoroastrians thought that mixing pure and impure substances was sacrilegious, and since they considered the elements of earth and fire pure, they would have violated cleanliness taboos by allowing a corpse to be either interred in the ground or cremated. This was because believers thought that after death, corpse demons (known as _nasu_) entered into and contaminated the deceased’s body. The solution that developed was “sky burials,” in which cylindrical towers (called “Towers of Silence,” but more properly known as _dokhma_) were built to expose a corpse to the air for quick eradication. The tower shown in the first photo is from Yazd, Iran. The second and third images are drawings illustrating the inside of the tower, which had three concentric circles to arrange bodies (children for the innermost ring, then women, and men in the outermost). You can see a bird’s-eye view of one of these _dokhma_ in the last photo. Between vultures and the sun, a body could disintegrate remarkably quickly.
